Apparatus for treating pulverized material



G. H. FRASER. APPARATUS FOR TREATING PULVERIZED MATERIAL.

APPLICATION TILED AUG-17.1918.

Patented July 26, 1921.

Fi i

. pulverizer for further screening. 'coarse screen is used to prevent the coarser HOLT FRASER, OF BROOK LYN NEW YORK.

APPARATUS FOR TREATING PULVERIZED MATERIAL Specification of Letters Patent. I Patented J l 26, 1921 Original application filed September 25, 1912, Serial No. 722,233. Divided and this application filed August 17, 1918. Serial No. 250,279.

To all whom it may concern: a

Be it knownthat I, 'Gnonen HOLT FRASER, a citizen of the United States, residing in the borou h of Brooklyn, county-ofKings, city and State of New York, United States of America, have invented certain new and useful Improvements in Apparatus for Treating -Pulverized Material, (being a division of my a lication filed September 25, 1912, Serial R12). 722,233,) .of which the following is a specification.

This invention relates to means for treating' finely divided material, or .mixtures of various pulverized substances, and to grinding, screening and mixing the same, and aims to provide improved means especially applicable to carrying out the improved methods set forth.

Hereto-fore it has been common to pulverize mixed materials of different physical characteristics or different specific gravity,

to grade the material according to size so that that material too large for pulverizing should be separated from that to be fed to the pulverizer, and that sufficiently pulverized material should beseparated for subsequent treatment. -Ordinarily a coarse screen or grizzly is used to remove the coarsest'material, and a fine screen or air separator is used to extract the powder, the intermediate-material being returned to the material from wearingthe finer separator, andits product maybe mixed with the reject of the latter for return to'the pulverizer after the fine separator has operated on the material.'

The coarse material or mixture is supplied from a bin or suitablesource, and the fine material is removed as, made to a bin or suitable discharge. The various successive operations are effected by suitable ap paratus arranged in the desired order and connected by any usual means for delivering from one to another. 1

In such operations difiiculties have arisen from the liability of the mixture to change in proportions at different times, especially when one ingredient is lighter than another or of different physical characteristics.

This changing of the relative percentagesof the different materials in-the mixture af fects the chemical qualities of the mass, and

The

coarse material and intermediate materialv difiiculty sometimes re-.

injuriously affect the operation of the apparatus, as well'as causing variations inthe proportions of. the mixture.

. This invention aims to provide a method whereby material can-be pulverized and separated with more economy of space and power than heretofore and without materially altering the character of the mixture, whereby pulverization can be effected with greater uniformity, and whereby the operation of pulverizmg and separating material may be automatically regulated by, the material being treated. 1

It also aims to'provide improved apparatus for pulverizing, separating and treatlng finely divided materlal or mixtures.

' 0- this end incarrying out the preferred form of the improved process, the ulverized material. is withdrawn from t e pulverizer' with the intermediate materialby gravity as fast as discharged and is imme- ,diately separated and removed as finished in quantities corresponding with the quantities of fresh material introduced for treatment, the proportions bein continuously maintained so that the material under treatment shall always be under uniform conditions, and the introduction of new material is automatically controlled by the presence of intermediate material, so that while intermediate material is present in the sys 'tem to the desired extent, the supply of fresh material is controlled by it to the extent desired to insure the finishing of the intermediate material present before ingress of fresh material. The escaping finished 'material controls the supply of fresh ma terial, and the intermediate material present only is elevated and refed to the pulverizer, and this 'refed material re lates the entrance of fresh material, T e effect of this is that the quantity of material being treated is maintained s0 uniformly that substan tially the same conditions prevail throughout treatment and its treatment must be completed before additional material can enter, thus precluding important changes pulverizer, a coarse screen,

in the percentages of the materials consti-' tuting the mixture, since the charge under treatment must be disposed of before additional material can be treated, while the material as finished is continuously withdrawn and is continuously re laced by the automatic control of the fres su ply, and any unnecessary lifting of finishe material is avoided.

Where the separation of finished material is efi'ected by a fluid current or air separator and the materials differ greatly in specific gravity, this precaution against changing of the mixture is especially important, as in such instances the air separation would tend to remove the lighter material from the heavier regardless of fineness, in case a continuing suppl of material were available before all 0 the material present had been pulverized.

This' invention also provides im' roved means for carrying out the improve process, which means preferably comprise a a fine separator, a supply bin, an elevator, and means connectin these parts in' succession to effect the desire results.

In the accompanying drawings Figure 1 shows the preferred utilization of the improved process, and the preferred embodiment of the improved apparatus, and is a vertical axial section 0 a pulverizing,

screening, separating, and discharging system, especially applicable for carrying out these improvements, the view being cut approximately on the line 1-1 of Figs. 2 and 3 looking in the direction of the arrows; Fig. 2 is a in mentary vertical section thereof cut at rig t angles to Fig. 1 a3) roximately on the line 2-2 of Fig. 3 an of the arrows, and Fig. 3 is a fragmentary horizontal section thereof cut approximately on'the line 33 of-Fig. 2 and looking .in the direction 'ofthe arrows. ,Referring to the drawings, pulverizer, B isa drive pulle therefor, C the grinding chamber thereo D the discharge conduit, E the inlet conduitthereof F a coarse screen, Gr its tailings'spout, an air se arator, I its tailings s ut, J its fine cham er, K its fine spout, L t e fine discharga M the coarse rock supply or feed bin, the feed hopper, O the feed regulating or controlling chamber, P the elevator or other means communicating between the parts 0 and E, and Q the supply regulator. The parts of the device shown may be of any suitable or usual construction and connected in any desired order or manner, but it is preferred to use a pulverizer of the ring and roll type in which the crushing members revolve on horizontal axes within the crushing chamber, and in which the material is centrifugally carried bythe ring A indicates a ,vibration or upward bump feedillg, elevating,

ooking 1n the direction ipaced apart adjacent face and free to .discharge in a vertical plane therefrom regardless of the fineness of the material, and to suitable source of power, and to drive the other parts from the pulverizer, connecting the parts in succession so that the operation of all will be coincident.

As shown, the mediately succeeds the pulverizer, and is disposed below the latter to receive the discharge therefrom, havin a revolving distributin disk It on' WlllCh this discharge falls an by whichit is spread horizontal y or thrown centrifugally to the outer edge of the screen, which latter is a vibratorynon rotativemember. 5

It is preferable to construct the screen in the shape of an inverted cone elasticall suspended from above by a'spring S, so t atit may descend under load or shock and will rise when released, and its u wardmovement will he suddenly arreste to give it a to jar material A lever or arm T hinged the screen and in the the disk R serves to out of its meshes. to the casing a above path of a projection on depress the screen when struck by the disk,

thus vibrating the screen.

Preferably the screen is provided with swinging or spring strikers U shown as both extending toward the shaft V of the disk It and movable into the path of swinging hammers'W thereon, so that they willbe struck thereby when the screen is depressed to agitate it for cleaning; The screen F is prefera ly extended within and discharges its fines onto the inner face of a revolving. s reader or distributer X, which is prefera lyan inverted cone .mounted on and revolving with the shaft V,

an. outlet surrounding and from the outlet of the screen The distributer X revolves with sufiito raise and distribute over its the material fine enough to pass and having cient speed upper edge the screen F, which material is thrown or,

spread horizontally against a deflector Y, from which it falls onto the receiving cone Z of the air separator, crossing the outlet thereof, so that the 'outfiowing current can blow the powdered material of desired fineness out of the falling material and into the settling or extracting chamber J of the air separator, the air from which returns within the apron I over thetailings cone 0, through the outlet d of the receiving cone, which parts afford between them inner and outer current passages, to the blades e of the blower f, which latter is preferably a conical wall surrounding the cone distributer X, and revolving therewith, and having radial blades between its inner face and the of the distributer. The re ceiving cone Z is yieldingly supported by springs {I so that it can drive the pulverizer from a coarse screen or grizzly imbe depressed until i its inner projections h are brought into the path of revolving strikers z to.v jar it.

The tailings cone communicateswith the cylindrical upper end of the spout I, which end surrounds and is concentric of the'coarse spout G, which latter receives the coarsematerial from the coarse screen F, The

distributer or cone X has bottom outlets j for any material failing to rise in the distributer, so 'that this material may drop through the bottom of the distributer and into the receiving cone Z and flow by gravity through the bottom outlet at thereof to the spout I. Allmaterial too large to be floated through the outlet, slides by gravity down the'receiving cone Z and escapes through its outlet to the s out I.

The s out discharges by gravity above and pre erabl verticall down intothe regulating cham er 0. I it is desired to use the "material flowing throu h the spout I, instead of to further grim? it, the door is in the bottom of this spout is turned up as shown in full lines so as to let the material in the spout, I-escape through the chute l, but if this material is to be reground, this door is closed as shown in dotted lines and the material enters the regulating chamber with the coarse material from the spout G.

The regulating chamber 0 discharges its material by gravity through a bottom outlet m to the boot of the elevator P, which "raises the material? to the feed inlet E, so that there is an endless circuit communicating through the pulverizer, the screen, the separator and the elevator back to the pulverizer, through which the coarse reject from the screen and the intermediate reject from the separator may be continually re-fed to the pulverizer without the necessity of also lifting the finished material, so that this material will be re-fed for re-grindin with the minimum of lifting power expen iture. The fine material! settling in' the dust chamber J flows into its spout K and escapes therefrom to the fine bin L.

The fresh feed from the chamber M flows past a gate n and a rock crusher or crushin roll 0 to the feed chamber N, from which it passesthrough outlets p to the regulating chamber 0. These outlets referabl have I I adjustable lips 9 within t e cham er 0 which extend inwardly, so that, the angle from the top of the outlet ;0 to the edge of the lip or shelf (1 is adjustable to control fiowof the material escaping from the feed bin. The feed bin surrounds one or more sides of the regulating bin and has several outlets thereto, preferably one. on each of tailings inlets L an The regulating bin is similar to a vertical conduit chute, and its inlet for intermediate and coarse material is above the inlets for fresh material, and its outlet is below theseinlets. The intermediate material falls into the regulating chamber, and if it is not removed through the outlet therefrom by the elevator as rapidly as it enters, it fills up this chamber until it rises above the outlets p of the feed bin, whereupon the intermediate material in front of these outlets arrests flow of fresh material from the feed bin, which it does by closin the outlets therefrom. The removal of t e intermediate material below these outletspermits this flow to automatically occur until it has sufficiently filled the 'regulatin chamber to again prevent inflow thereto. T he removal of material by the elevator through the outlet from the regulating chamber progresses uniformly, and so long as there is any material in the regulating chamber above the fresh feed outlets, entrance 'of fresh feed is prevented. The supply of intermediate material thus controls ingress of fresh material, and in this manner the continual grinding of intermediate material is insured,

laterally intermediate of its bottom outlet m and its upper sugeposed fine and coarse ,the' excessive removal of alighter ingredient from the mixture by the air separator will be precluded, since the heavier ingredients left in the system will prevent infeed of fresh material until the air separator removed a suflicient quantity to permit the infeed of fresh material to automatically resume. c

Should the escape of finished material be uninterrupted, the entrance of fresh material can be automatically controlled b the arrangement described, but it is pre erred to furtherinsure that the fresh material supplied to the system shall accord with the removal" of finlshed material therefrom. This preferably is accomplished by utilizing the, weight of fine material removed to control the supply of fresh material to the feed bin, and vice versa. As shown, the finished.

material spout K discharges intov a weighing bucket 1* through a gate 8 which is con-" trolled by a weighing; device t, and this bucket and gate are connected by a lever u with a gate w and bucket w for the feed bin, which are controlled by a weighing device 2 The bucket :12 is shown as su ported from its weighing device by the trip catch 2, so that the gate to is open and fresh material for the feed bin is entering the bucket :10. When the desired quantity has entered the bucket its weight tilts the beam until the trip catch releases, whereupon the bucket ra idl falls, closing the gate to to revent urt er infeed of fresh material, t1 ting the lever u to raise the bucket r and open the gate 8 until its trip catch a engages and supports this bucket, the bucket a: dumping and the bucket 1' closing, all according to any well known method of automatic weighing, of which the parts illustrated are intended to be diagrammatic representations; The bucket m will ,dischar e its weight load of fresh feed into the eed bin N and the bucket 1' will collect an equal load of finished material from the spout K, after which the operation will be reversed, the bucket 1' dumping its load into the fine bin L and closing the fine outlet and restoring the bucket a: and opening the feed outlet.

As shown, the elevator is driven from the pulverizer by a belt a and the distributer for the coarse screen and blower for the air separator, as well as the feeder for the fresh rock, are driven by a belt 12 therefrom, so that all movable parts of the system coincide with the pulverizer in operation, thus assuring stoppage of all in case of stoppage of the pulverizer, which prevents undue accumulation in any part ofthe system.

In this manner an automatic mechanical uniformity of supply and removal may be attained to prevent variations in operating conditions and minimize resulting changes.

In operating according to my improved process, one or several grades of the treated material, or of the material in process of treatment, will be utilized to control the feed of other grades of material or of fresh material, according to the requirements of the particular process or conditions of use. The coarser material bein projected through the intermediate materia w ll materially reduce the tendency of the material to segregate according-to size within the regulating chamber. The control of the fresh or coarse material by the intermediate material will insure the precedence to the latter in treatment, and greatly diminish tendency to variations in the percentage of ingredients in the mixture if a mixed material is being treated.

In using my improved apparatus the circular orconical vibrator movabl and yieldingly mounted in the screen w1ll be easily kept from clogging, and being nested or positloned within the conical redistributing disk, will occupy comparatively little space, and the distributing disk being likewise nested within the receiving cone of the air separator, and the blower of the latter being disposed in conical arrangement between the distributing cone and the receiving cone,

cations as circumstances or arators ma be employed, if desired.

will further minimize the space required for these several parts. The revolving striker in conjunction with the yielding and movably mounted receiving cone, will aid in keeping the cone clean, thus reducing the steepness necessary therefor.

It will be seen that this invention provides improvements in processes of treating materials which can be variously and advantageously availed of'in whole or in part, and it will be understood that the invention is not limited to the particular details of arrangement, application or use set forth as constituting its preferred adaptation, since it can be employedin whole or in part according to such modifications and in connection with such devices as circumstances or the judgment of those skilled in the art may dictate, without departing from the spirit of the invention; and it will also be understood that the improvements in apparatus this invention provides are not limited to the particular details of construction, arrangement and combination set forth as constituting the preferred form thereof, since these improvements may be used in whole or in part according to such modifithe judgment of those skilled in the art may dictate, without departing from the spirit of the invention.

For example, in practising the improved process any suitable means for communicating between the parts in any desired successive stage may be employed.

While these improvements in apparatus 100 include in their preferred form circular or conical devices nested within one another for compactness, and having annular communicating ducts and contracting annular outlets, it will be understood that it is not essential 106 that these be usedin practising parts of the invention, since the elements may be individualized and connected in any suitable arrangement, or any suitable grizzlies or sep- While t e regulating hopper or bin is shown as disposed below all the parts and as feeding from its bottom to the mill throu h the medium of the elevator, and the p urality of hoppers or bins for different grades of material to be fed are shown as beneath the mill, and the feed bin as surrounding the regulating bin, instead of these parts being above the mill and the re lating bin discharging directly into the atter, it will be understood that the arrangement shown is not essential, being preferred for compactness and convenience of access, and that the plurality of bins may be located as desired,

and the connections correspondingly arbeingconstructed and connected in proper manner to enable the grade of material which is to have precedence to interrupt or plementary portion of said path and const1tut1ng a way for material in said path,

means for causing material to circulate through said path, means for withdrawing fine material from said path, means for withdrawing medium material from said path, means for progressing the residue of partially ulverized material in such path and vpast sa1d inlet, means for supplying through said inlet fresh material to be pulverlzed,

and means for causing such residue of unpulverized material in said path to control lnflow through said inlet of such fresh material.

2. In combination, means for roducing fine material comprising means a ording an endless path afi'ording an inlet for pulverulent material and an outlet for fine material and'comprising a separator having a separatingchamber affording a complementary portion of said path and constituting a way for material in said path, means for withdrawing medium material from said path, means for causing material to circulate through said path, means for withdrawing fine material from said path, means for progressing a residue of coarse material in said path past 'said inlet, means for supplying through said inlet additional pulverulent material, and means for causing such residue material in said. path to control inflow thrlough. said inlet of such additional mater1a a 3. In combination, means affording an endless path for pulverulent material. af-

fording an inlet and an outlet and comprismg conveying means having a chamber affording a complementary portion of said path and constituting a wa for such material in said path, means or causing material to circulate through such path, means for withdrawing from said path a fine portion and a medium portion of such material circulating through said path, means for progressing in said path the residue of such material therein past said inlet, means for supplying through said inlet additional material to said path, and means for causin such residue material in said path to contro inflow through said inlet of such additional material.

4. In combination, .means afi'ording an 4 endless path for pulverulent material affording an inletand. an outlet and comprising elevating means having a vertically extending chamber afi'ording a complementary rtion of said path and constituting-a way or. such materlal in saidpath, means for causing material to circulate through said path, means for withdrawing through saidoutlet a fine portion and a medium portion of such material from said path, means for progressing the residue of such material in said ath past said inlet, means for supplying t rough said inlet additional material to said path, and means for causing such residue materialin said path to controlinflow through said inlet of additional material.

5. In combination, means for producing pulverized material comprising means 'affording an endless path for material to be pulverized, comprising a crushing chamber affording a complementary portion of said path and constituting a wayfor material in said path, an elevator for elevating material in said path having a vertically extending chamber affording a complementary portion of said ath and constitutin a way for material -1n said path, means or causing material to circulate through said path,

means for separating fine and medium material from such material in said path, means afl'ordin an outlet for fine material from said pat means in said path between said crushlng chamber and elevator affording an inlet to said path for additional material, means for progressing such residue of material in said th past said inlet, means for supplying t ro h said inlet additional material to said pat and means for causing such residue material in said path to control inflow through said inlet of such additional material.

6. In combination, means for separating fine material comprising means afiordlng an endless path for pulverulent material to be separated and 'comprislng a separator having a separating chamber affording a complementary portlon of said path and constitutin a way for such material in sa1d path, e evating means for elevating material in said path comprising a vertically extending chamber affording a complementary portion of said path and constituting away for such material in said ath, means for causing such material to clrculate through said path, means affording outlets for medium and for fine material from said path communicating with said path between said separator and said elevator for withdrawing from said path fine material separated from the material in said path, means afiording an inlet to said path between'said' elevator and said separator, means for pro ssin the residue of such material in sa1d pat past said inlet, means for sup lying to said lent material, and

I rating means for separatin means for causing such said path tocontrol in inlet of such addltional residue material 1n flow through said material.

=7, In combination, means afiording an endless path afiording an inlet for pulverulent material and an outlet for fine material and comprising elevating means having a chamber affording a complementary portion of said path and constituting a vertically extending way for such material in said path, separating means for separating fine and medium material from the material in said path having a downwardly extending chamber affording a complementary portion of said path and constituting a gravity way: for downward flow of material 1n said path, means for progressing the residue of material in said path .b gravity past said inlet for controlling in ow through said inlet, and means for introducing additional material into said path by gravity through said inlet 8. In combination, means afi'ording an endless path for pulverulent material and comprising elevating means for elevating such material having a vertically extending chamber affording a complementary portion of said path and constituting an upward wa for such material in said path, sepacoarse material from such material in said path havlng a chamber afiording a com lementary portion of said path and constituting a gravity way for material in said path, means between said elevating means and said separating means affording a conduit for coarse material aflording a complementary portion of said ath, means for withdrawing from said pat separately fine and medium material constituting the residue of such material in said path through said outlet, means for rogressing such coarse material in said pat past said inlet, means for introducing into said path through said inlet additional material, and means for causing such coarse material in said path to control inflow through said inlet of such additional material.

9. In combination, a separator for separating fine material from pulverulent ma terial having an inlet and having an outlet for fine material and having an outlet for medium material and having an outlet for coarser material, an elevator communicating between said latter outlet and said inlet for raising coarser material discharged through said latter outlet and returnin it to said inlet, and means for feeding a diditional pulverulent material to be separated to said separator controlled by the material discharged through said outlet for coarser material.

10. In combination, a separator for sepa- I rating fine material from pulverulent material having an inlet and having an outlet for discharging fine material and having an outlet for medium material and having an outlet for coarser material, and means for 'feedin pulverulent material to be se arated to sai separator controlled by the ne material discharged through said outlet for fine material.

In witness whereof, I have hereunto signed my name in the presence of two subscribing witnesses.

GEORGE HOLT FRASER.

Witnesses:

EDMUND J. FENN,

HERBERT J ..RIBBER. 

